		function doResetFrame(){
			//parent.document.getElementById("bottomFrameSet").cols="184,*"
		}
		
		function makeSubMenu(menuID){
		    switch(menuID)
			{
				case "000" :
			    {
			    	//parent.document.getElementById("bottomFrameSet").cols="0,*"
					//parent.document.getElementById("mainFrame").src="personnel_portal_bottom.html";
				}break;
				case "001" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left.html";
						parent.document.getElementById("mainFrame").src="default/default.html";
				}break;
				case "002" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left_2.html";
					parent.document.getElementById("mainFrame").src="default/default_2.html";
				}break;
				case "003" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left_3.html";
					parent.document.getElementById("mainFrame").src="default/default_3.html";
				}break;
				case "004" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left_4.html";
					parent.document.getElementById("mainFrame").src="default/default_4.html";
				}break;
				case "005" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left_5.html";
					parent.document.getElementById("mainFrame").src="default/default_5.html";
				}break;
				case "006" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left_6.html";
					parent.document.getElementById("mainFrame").src="default/default_6.html";
				}break;
				case "007" :
			    {
			    	doResetFrame();
					parent.document.getElementById("leftFrame").src="left/left_7.html";
					parent.document.getElementById("mainFrame").src="default/default_7.html";
				}break;

			}
		}
		
		function test(o){
			//无需遍历所有字节点得到对象	
			var cc = document.getElementById('current_a');  //得到当前对象
			//如果当前对象等于o，就不管
			if(cc==o)return;
			//否则，就把原先的样式置空，而且把现在的样式设置
			if (cc){
				var thisClassName = cc.parentNode.className;
				cc.parentNode.className = thisClassName.substring(0,thisClassName.indexOf('_over'));
				//cc.parentNode.className = "menu4font"; 
			  	cc.id="";
			}
			var oClassName=o.parentNode.className;
			o.parentNode.className = oClassName+'_over';
			//o.parentNode.className = "menu4font_over"; 
			o.id='current_a';
			o.blur();//失去焦点
		}
		
		function init(){
			var aa=document.getElementsByTagName('a');	
			for (var i=0;i<aa.length;i++)
				aa[i].onclick=function(){test(this);};  //当单击按钮时的反应
			test(document.getElementById("first"));//初始化
		}
		
		window.onload = init;
    
    	function doSwitchRole(obj){
    		if(obj=='student'){
    			location.href='head.html';
    			makeSubMenu("112");
    		}
    		else if(obj=='teacher'){
    			location.href='teacherHead.html';
    			makeSubMenu("001");
    		}
    		else if(obj=='admin'){
    			location.href='adminHead.html';
    			makeSubMenu("311");
    		}
    	}